 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Medical Forum / Diseases and Disorders / Alzheimer's / August 2004Brain ferrous toxic iron
<<snip>> presence of hemosiderin together with ferritin in the pathological brains <<snip>> J Struct Biol. 2004 Aug;147(2):166-78. Related Articles, Links Electron nanodiffraction and high-resolution electron microscopy studies of the structure and composition of physiological and pathological ferritin. Quintana C, Cowley JM, Marhic C. Instituto de Microelectronica de Madrid. C.S.I.C., 8 Isaac Newton, PTM, 28760 Tres Cantos Madrid, Spain. Structures of core nanocrystals of physiological (horse spleen, human liver, and brain) and pathological human brain of patients with progressive supranuclear palsy (PSP) and Alzheimer's disease (AD) ferritin molecules were determined using electron nanodiffraction and high-resolution transmission electron microscopy. The poly-phasic structure of the ferritin cores is confirmed. There are significant differences in the mineral composition between the physiological and pathological ferritins. The physiological ferritin cores mainly consist of single nanocrystals containing hexagonal ferrihydrite (Fh) and hematite (Hm) and some cubic magnetite/maghemite phase. In the pathological cores, Fh is present but only as a minor phase and Hm is absent. The major phases are a face-centered-cubic (fcc) structure with [Formula: see text] nm and a high degree of disorder, related to wustite, and a cubic magnetite-like structure. These two cubic phases are also present in human aged normal brain. Evidence for the presence of hemosiderin together with ferritin in the pathological brains is deduced from the similarities of the diffraction patterns with those from patients with primary hemochromatosis, and differences in the shapes and protein composition of the protein shell. These findings suggest a disfunction of the ferritin associated with PSP and AD, associated with an increase in the concentration of brain ferrous toxic iron. PMID: 15193645 [PubMed - in process] -------------------------------------------------------------------------- ------ Who loves ya. Tom  SignatureJesus Was A Vegetarian! http://jesuswasavegetarian.7h.com Man Is A Herbivore! http://pages.ivillage.com/ironjustice/manisaherbivore DEAD PEOPLE WALKING http://pages.ivillage.com/ironjustice/deadpeoplewalking doe you are an idiot > doe you are an idiot > > Yes I agree with you,the mans a fool! he pedals his old iron on many newsgroups ,according to him all of our diseases are caused by the presence of iron,everything from in growing toe nails to Alzheimer's.makes you wonder how the human species' ever evolved with this" poisonous "iron everywhere in plants and animals.And it is these sort of crackpot ideas that cause anxiety to many people who are in a vulnerable and emotional situation looking after their family ,but of course he says that Jesus was a vegetarian! what nonsense,Christ frequently referred to sheep ,Oxon, fishes,he even told the fishermen where to cast there nets. I know I'm getting away from the point ,but don't get drawn into believing his rusty theories john.m >Subject: Re: Brain ferrous toxic iron Ann N Y Acad Sci. 2004 Mar;1012:179-182. Related Articles, Links Oxidative Stress and Redox-Active Iron in Alzheimer's Disease. Honda K, Casadesus G, Petersen RB, Perry G, Smith MA. Institute of Pathology, Case Western Reserve University, Cleveland, Ohio, USA. Many lines of evidence indicate that oxidative stress is one of the earliest events in the genesis of Alzheimer's disease (AD). Iron is a transition metal capable of generating hydroxyl radicals, the most potent reactive oxygen species. Consequently, a disruption in the metabolism of iron has been postulated to have a role in the pathogenesis of AD. Indeed, both senile plaques and neurofibrillary tangles, the major pathological landmarks of AD, as well as neurons in the earliest stages of the disease, show elevated iron deposition. However, it is clear that the iron bound to lesion-associated proteins such as amyloid-beta and tau plays only a minor, late role in the disease, with the RNA-associated iron found in the neuronal cytoplasm occurring early and being of paramount importance. In this regard, it is probably not surprising that there is significant oxidation of cytoplasmic RNA among the populations of neurons vulnerable to AD. In this review, we consider the role of iron-induced oxidative stress as a key event in AD pathophysiology. PMID: 15105265 [PubMed - as supplied by publisher] -------------------------------------------------------------------------- ------ Who loves ya. Tom >Subject: Brain ferrous toxic iron Free Radic Biol Med. 2001 Feb 15;30(4):447-50. Related Articles, Links Redox-active iron mediates amyloid-beta toxicity. Rottkamp CA, Raina AK, Zhu X, Gaier E, Bush AI, Atwood CS, Chevion M, Perry G, Smith MA. Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA. While amyloid-beta toxicity is mediated by oxidative stress and can be attenuated by antioxidants, the actual biochemical mechanism underlying neurotoxicity remains to be established. However, since aggregated amyloid-beta can interact with transition metals, such as iron, both in vitro and in vivo, we suspected that bound iron might be the mediator of toxicity such that holo- and apo-amyloid would have differential effects on cellular viability. Here we demonstrate that when amyloid-beta is pretreated with the iron chelator deferoxamine, neuronal toxicity is significantly attenuated while conversely, incubation of holo-amyloid-beta with excess free iron restores toxicity to original levels. These data, taken together with the known sequelae of amyloid-beta, suggest that the toxicity of amyloid-beta is mediated, at least in part, via redox-active iron that precipitates lipid peroxidation and cellular oxidative stress. PMID: 11182300 [PubMed - indexed for MEDLINE] -------------------------------------------------------------------------- ------ Who loves ya. Tom SignatureJesus Was A Vegetarian! http://jesuswasavegetarian.7h.com Man Is A Herbivore! http://pages.ivillage.com/ironjustice/manisaherbivore DEAD PEOPLE WALKING http://pages.ivillage.com/ironjustice/deadpeoplewalking |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.